The welding parameters of single torch external welding machine mainly include wire feeding speed, travel speed, oscillation width, oscillation frequency, left and right dwell time, torch vertical adjustment, torch horizontal adjustment range. The process of internal butt joint device + single welding torch is adopted. The wall thickness is designed to pass through the steel pipe with the maximum wall thickness of 38mm used in the crossing, and the single U-shaped compound groove is adopted. According to trigonometric function calculation and considering the group gap, the maximum width of single U-shaped compound groove is 12.0mm for the pipeline with 38mm wall thickness.

Internal line up clamp+single torch external welding machine is applied, max. pipe wall thickness is 38mm, max. width of U shaped bevel is 12.0mm. In consideration of efficiency of narrow gap bevel welding, Max. oscillation width is set to be 13mm for last pass of filling and capping pass (single pass is applied for capping instead of multiple pass).

Max. travel speed is set to be 1.5m/min, Max. wire feed speed is set to be 20.0m/min, by reference of travel speed 1.35m/min and wire feeding speed 14.22m/min for downhill welding of hot pass with solid wire, also in consideration of faster travel speed and wire feeding speed for hot pass welding of higher grade steel in the future.

Min. travel speed is set to be 0.1m/min, Min. wire feeding speed is set to be 2.5m/min, by reference of Min. travel speed 0.15m/min and Min. wire feeding speed 6.1m/min for uphill welding with flux cored wire, also in consideration of slower travel speed and wire feeding speed for welding of other grade steel in the future.

On the whole, travel speed range of single torch external welding machine is set to be 0.1-1.5m/min, wire feeding speed rang is set to be 2.5-20.0m/min.